Index mechanism



April 26, 1938.; K Mum 2,115, 5

INDEX MECHANI SM Filed Feb. 5, 1938 Patented Apr. 26, 1938 PATEN T OFFICE INDEX MECHANISM Kenneth 0. Allison, Arlington Heights, 111., assignor to Oak Manufacturing Company, Chicago, 111., a corporation of Illinois Application February 5,1938, Serial No. 188,874

4 Claims.

This invention relates to an index mechanism particularly for use in connection with electric switches. An object of this invention is to devise such an index mechanism which will be simple,- cheap and effective.

Referring to the drawing:

Figure 1 shows aside view of the index mechanism forming part of a bank of switches. v

Figure 2 is a section on line 22 of Figure 1.

Figure 3 is a section on line 33 of Figure 2.

Figure 4 is a section on line 4-4 of Figure 3.

Figure 5 is a section on line 5-5 of Figure 2.

Referring to Figure 1, a shaft [0 has a portion thereof ll mutilated to provide a plurality of flats extending through switch sections l2 and I3. These sections comprise stators having stator contacts l5 and rotors carrying suitable contacts not shown. This type of switch is disclosed in United States Patent 2,012,492 to Arnold. The stator sections I 2 and I3 are maintained in spaced relation by sleeves l6 and I 1 through which bolts I 8 and I9 are threaded. Between switch section I2 and the frontend of bolts l8 and I9 are sleeves 20 and 2| at the ends of which is an index plate 25. Nuts .26 on bolts I 8 and I9 serve to maintain the switch assembly intact.

As shown in Figure 2, index plate is of a generally circular shape and is provided with extensions 28 and 29 through which the bolts 18 and I 9 extend. Index plate 25 has maintained therein at the center a bushing 30, the inner end of which is bent over at 3| to make a rigid assembly. Bushing 30 has the front part thereof threaded and is adapted to have a nut "cooperate with the threaded portion and a shouldered part 33 to maintain the entire switch on a panel. Shaft I 0 is rotatively coupled within bushing 30 and is locked against longitudinal movement by means of a C washer 36 disposed in a suitable slot 3'! in the shaft adjacent the front end of bushing 30.

It will be noted that the flat portion ll of shaft ll begins just as the shaft emerges beyond peaned portion 3| of the bushing. Locked to the shaft at this portion thereof is a spring plate 38 having a generally circular shape. Spring plate 38 is locked to shaft H by forcing the metal into grooves 39 in the shaft. Plate 38 has an. extension 4|. Shaft l I extends through plate 38 at an eccentric part thereof, preferably opposite tongue 4| of the plate. Between shaft H and tongue 4| an irregular generally heart shaped aperture 43 is cut away inthe spring plate and a tongue 44 is bent down opposite tongue 4| at the tip of the heart shaped aperture to extend toward index plate 25.

The index plate itself is provided with a plural- "ity of index indentations here shown as spaced apertures 46 disposed on the arc of the circle around shaft II and separated by protuberances 41 wherein the metal of the index plate is forced toward the spring plate. As is clearly evident in the drawing, the index indentations and protuberances are all on the arc of a circle and are adapted to cooperate with finger 44 bent from the body of the spring plate 38.

In order to limit the angle of rotation of the mechanism, a pair of cars 50 and 5| are bent up from index plate 25 at spaced intervals just beyond the circle whose arc is traversed by the finger 44. These two fingers or stops 50 and 5] cooperate with extension 4| to limit the swing of the shaft.

Because of the manner in which spring plate 38 is cut, it has been found that a cheap and effective spring is obtained. This plate may be made of spring steel or any other suitable material and is preferably rigidly secured to the shaft so as to be locked against both longitudinal and rotational movement.

- What is claimed is: V

1. An index mechanism comprising an index plate having a shaft rotatably mounted therein, said index plate having a plurality of index indentations and a spring member rigidly coupled to said shaft, said spring member having a generally circular shape and mounted upon the shaft in an eccentric position, and a tongue bent over I the .plate adapted to cooperate with the index indentations.

2. The structure of claim 1 wherein said index spring has a generally heart shape cut out between the tongue and shaft with the widest portion of the aperture nearest the shaft.

3. An index mechanism comprising an index plate having a shaft rotatably mounted therein and having a plurality of index indentations and a spring circular plate eccentrically mounted on said shaft and having a tongue extending beyond the circular portion and a second tongue formed out of the material between the first tongue and the shaft mounting, said second tongue cooperating with said index indentations, said index plate having a plurality of stops with said first tongue cooperating with said stops to limit the operating range of the shaft.

4. The structure of claim 3 wherein said spring plate has a heart shape cut out between the shaft and the second tongue with the widest portion-of the cut out nearest the shaft.

KENNETH C. ALLISON. 

